Couplings for optical fiber communication systems are well known. It is often necessary to arrange a plurality of optical fiber couplings in a panel in order to facilitate multi-fiber connections. Desirably, devices for holding couplings are mounted in the panel, but the couplings themselves are not connected to incoming or outgoing fiber paths until actually needed to provide service. Devices which are mounted in a panel to accommodate interconnections are commonly referred to as "buildout blocks" or, simply, "buildouts."
As is known and understood by those skilled in the art, it is common practice in the optical coupling art to terminate a length of optical fiber with a coupling. Once such type of optical fiber coupling which is used for terminating and connecting two optical fibers is referred to as an ST.RTM. coupling. ST.RTM. is a registered trademark of Lucent Technologies Inc. The ST.RTM. coupling is disclosed, for example, in U.S. Pat. No. 4,934,785, which issued on Jun. 19, 1990 to T. D. Mathis and Calvin M. Miller. A buildout for an ST coupling is described in U.S. Pat. No. 5,067,783, which issued on Nov. 26, 1991 to N. R. Lampert. Another type of optical fiber coupling is the SC type coupling that is shown and described in U.S. Pat. No. 5,212,752, issued to D. L. Stephenson, et al. In U.S. Pat. No. 5,274,729, which issued to King, et al. ("the '729 patent"), a variety of couplings for buildout systems are described.
In addition, in U.S. patent application Ser. No. 08/563,067, filed Nov. 27, 1995 by D. L. Stephenson, et al. a "shutter" used to close the end of a connector, in order to prevent dust from entering, is described.
As is understood by those skilled in the art, the couplings which mount in the panel are inserted from the front side of the panel and then they clip into the panel. From behind the panel a fiber optic cable which is terminated in a coupling having a ferrule is inserted. If the ferrule is not exposed, i.e., if it is enclosed in a sleeve, cleaning the end of the ferrule is extremely difficult if not impossible. Yet another problem with the couplings of the prior art is that they required the rotation of the buildout, while it was still in the block, in order to remove the buildout. The rotation of the buildout would damage the fiber end face if one of the two mated connectors was not removed.
In order to eliminate these problems, a buildout for an SC coupling has been developed. A problem with the buildout which is disclosed in the '729 patent is that its "footprint" does not fit within the Telecommunications Industry Association standard for SC couplings, FOCIS 3, Fiber Optic Coupling Intermateability Standard (TIA/EIA-604-3) which provides for the dimensions to be used by SC couplings. Accordingly, while the existing buildout works with SC couplings, which are panel mounted, if someone was to build a panel which complied with the minimum separations set for SC couplings, the SC buildout coupling of the prior art could not be used, since adjacent couplings would not fit on the panel. In view of the above, it would be desirable to have an SC coupling which could be panel mounted and which would provide a buildout whereby the cleaning of the ferrules could be facilitated.